PSLE
Four girls, Abi, Barbara, Olivia and Nora raised money for a charity. Abi and Barbara raised a total of $116. Together, Barbara, Olivia and Nora raised a total of $256. The total amount of money raised by all 4 girls is 5 times the amount that Barbara raised. How much money did Abi raise?
Amount that Barbara and Abi raised = $116
Amount that Barbara, Olivia and Nora raised = $256

Barbara is the repeated identity.

Barbara + Abi = 116 --- (1)
Barbara + Olivia + Nora = 256 --- (2)

Amount that Barbara raised = 1 u
Amount that 4 girls raised = 5 u

(1) + (2)
(Barbara + Abi) + (Barbara + Olivia + Nora) = 116 + 256
Barbara + 4 girls = 372
1 u + 5 u = 372
6 u = 372

1 u = 372 ÷ 6 = 62

Amount that Abi raised
= 116 - 1 u
= 116 - 62
= $54

Answer(s): $54